Wideband DOA estimation for nonuniform linear arrays with Wiener array interpolation

Abstract

Coherent wideband DOA estimation for non-uniform linear arrays (NLA) is considered. Array interpolation is used for two mappings. In the first mapping, NLA is mapped to a uniform linear array with the same array aperture. In the second mapping covariance matrices for each frequency bin are mapped to a single one at the center frequency for coherent DOA estimation. A Wiener formulation is used for array interpolation where both signal and noise powers are estimated with maximum likelihood method. Different approaches are compared and the advantages of wideband processing versus narrowband processing are outlined. The accuracy of the SNR estimation is high and it is shown that Wiener array interpolation significantly improves the DOA estimation performance in both narrowband and wideband processing.